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921.
Hydrobiologia - As lakes warm worldwide, temperature may alter plankton community structure and abundance by affecting not only metabolism but also trophic interactions. Siberia’s Lake Baikal...  相似文献   
922.
Every year, 2 million women reach menopause in the United States, and they may spend 40% or more of their life in a postmenopausal state. In the years immediately preceding menopause—known as the menopause transition (or perimenopause)—changes in hormones and body composition increase a woman’s overall cardiometabolic risk. In this narrative review, we summarize the changes in weight, body composition, and body fat distribution, as well as the changes in energy intake, energy expenditure, and other cardiometabolic risk factors (lipid profile, glucose metabolism, sleep health, and vascular function), that occur during the menopause transition. We also discuss the benefits of lifestyle interventions in women in the earlier stages of menopause before these detrimental changes occur. Finally, we discuss how to include perimenopausal women in research studies so that women across the life-span are adequately represented.  相似文献   
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924.
ObjectiveIn patients with primary aldosteronism, adrenal venous sampling (AVS) is performed to determine the presence of unilateral or bilateral adrenal disease. During AVS, verification of catheter positioning within the left adrenal vein (AV) and the right AV by comparison of AV and inferior vena cava (IVC) cortisol levels can be variable. The objective of this study was to determine the utility of AV epinephrine levels in assessing successful AV cannulation.MethodsThis was a single institution, retrospective review of patients who underwent AVS with cosyntropin stimulation for primary aldosteronism between 2009 and 2018. Successful cannulation of the AV was defined by an AV/IVC cortisol ratio selectivity index (SI) ≥3:1. Epinephrine thresholds to predict catheter placement in the AV were determined using logistic regression. The calculated epinephrine thresholds were compared with previously published thresholds.ResultsAVS was performed on 101 consecutive patients and, based on the SI, successful cannulation of the left AV and right AV occurred in 98 (97%) and 91(90%) patients, respectively. The calculated optimal epinephrine threshold to predict AV cannulation was 364 pg/mL (sensitivity, 92.1%; specificity, 94.6%) and the calculated optimal AV/IVC epinephrine ratio threshold was 27.4, (sensitivity, 92.1%; specificity, 91.3%). Among the 14 patients with failed AV cannulation, 3 patients would have been considered to have successful AVS using AV epinephrine levels >364 pg/mL and AV/IVC epinephrine ratio >27.4 thresholds.ConclusionObtaining 2 right AV samples routinely as well as AV and IVC epinephrine levels during AVS could prevent unnecessary repeat AVS in patients with failed AV cannulation based on cortisol-based SI <3:1.  相似文献   
925.
ABSTRACT.   Currently, the sex of Red-tailed hawks ( Buteo jamaicensis ) cannot be determined by in-hand methods. Males and females do not differ in plumage and overlap in size. We collected feather samples and morphological measurements from migrating birds at four sites in the western United States. Sex was determined for individual birds using sex-specific DNA markers and polymerase chain reaction was used to identify these DNA markers. Using discriminant function analysis, we created equations for determining the sex of Red-tailed Hawks using in-hand measurements based on the DNA-determined sexes. We formed two equations, one for adults that was 98% accurate, and one for hatch-year birds that was 97% accurate. The ability to determine the sex of western Red-tailed Hawks using morphological measurements will be useful to investigators examining possible intra- or intersexual differences.  相似文献   
926.
Systematic Parasitology - The striated darter (Etheostoma striatulum Page &amp; Braasch) is a rare fish species restricted to the Duck River system in Maury County, Tennessee, USA. In this...  相似文献   
927.
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